Screw Number: Double Screw Pump
Pump Shaft Position: Horizontal
Application: Sewerage Treatment, Food, Chemical
HS Code: 8413604090
Screw Suction Method: Double Suction
Certification: ISO, SGS
Thread: Double Thread
Mechanical Seal: Lubricating Oil
Transport Package: Wood Package
Shipbuilding: Be used as marine cargo pump, stripping pump, main engine lube oil pump, fuel transfer pump and marine ballast pump.
Oil fields: Be used as transfer pumps for conveying various oil products, diesel, crude oil, etc.
Thermal power plant: Be used as transfer pumps for conveying heavy oil and crude oil, heavy oil fuel, circulating water and water, etc.
Refinery: Be used as transfer pumps for conveying various heating oil, asphalt oil, tar and emulsion, etc.
Chemical: Be used as transfer pumps for conveying various resin, paint, glycerin, paraffin, circulating water and water, etc.
Food: Be used as transfer pumps for conveying alcohol, honey, sugar juice, toothpaste, milk, wine, vegetable oil, soy sauce and animal oil to the wineries, food factory, sugar refinery and cannery, etc.
1,Conveying liquid smoothly, no pulse, no stirring, little vibration and low noise.
2,The products possessed the advantages of good self-priming performance in the standard state, the net suction height is 8 meters and the self absorption time is 8-25 seconds.
3,The products can be stripping completely with stronger gas-liquid mixed transportation ability, which solved the problems of filling pipe air resistance of smoke discharging tanker and cavitation.
4,Using external bearing structure, the pump can transport various non - lubricating media because of simple structure and independent lubrication.
5,The biggest feature of product is transporting gasoline, ethanol, xylene and other volatile oil in the high temperature season, and food and a lot of corrosive mediums.
6,Using double suction structure, the rotor has no axial force.
7,No contact between two rotors for using synchronous gear transmission. Even the idling a pump, the machine can be safe in a short time.
Types (According to the screw and the material of pump body, 2CLG-type horizontal double-screw pumps is divided into four types)
1. 2CLG1 Type: The active and passive screw of pump are integral steel screw. It can be used as transfer pumps for conveying lubricating oil, diesel oil and residual oil, etc.
2,CLG2 Type: The active and passive screw of pump are sectional copper screw with steel core. It can be used as transfer pumps for conveying gasoline, kerosene, oil and other volatile oil, etc.
2CLG3 Type: The active and passive screw of pump are integral Stainless steel screw, the other parts are stainless steel casting or stainless steel plate welding. It mainly can be used as transfer pumps for conveying corrosive medium and liquid food.
2CLG4 Type: The active and passive screw of pump are sectional copper screw with stainless steel core. It can be used as transfer pumps for conveying common corrosive media, such as aviation kerosene.
Structure and working principle
1,Structure features:The structure of the pump is mainly composed of pump body, active and passive screw, shaft seals, bearing frame device, synchronous gear, safety valve and other components (see structure schematic drawing). There is no thread in the middle of the active and passive screw , but there are rectangular surface threads in the opposite direction from the left and right sides. The pump body, active and passive screw have a certain gap to ensure the self suction performance of the pump, active and passive screw tooth each other in rotating.
2,Operation principle:Starts the motor drives and drives active screw by the coupling, then active and passive screw makes meshing rotation and the both ends of pump suction occurs vacuum, medium is inputed the both ends of the pump through a pair of synchronous gears transmission. Finally, the medium is pushed the outlet of pump body under the spiral surfaces of the active and passive screw motivation.
3,Operational principle of safety valve:Safety valve is installed in the side of the pump body, its opening pressure(i.e. activated pressure) is the rated working pressure of pump 1.05-1.1 times. When the working pressure of pump exceeds this value, the safety valve core is rising automatically, so the pressure chamber of pump and inlet to each other mutually , forming a loop and the formation of internal circulation, then pump pressure will not rise, and will not make the pump overload. When the output line pressure is lower than the activated pressure, the the pump will continue to work normally. The double screw pump has no safety valve when the flowing is less than 12m3/h (including 12m3/h ), the user can be configured the safety valve on the oil pipeline according to your needs.
(Use methods and notes of the screw pump)
1.The flexible coupling should be used to connect the pump and the prime mover. No clamping phenomenon after installation, and the disalignment is not more than 0.10 millimeters.
2,The pump and the prime mover must be installed on the engine base with stiffness, so as not to affect the coaxiality and damage the main parts of the pump, thereby affecting the normal work of the pump.
3,For pump steering, in the face of the output shaft of the pump as a clockwise direction, and the the suction on the right side of the pump. For steering and suction of pump with special requirements( such as symmetrical pump), the customers need specify in order to process according to the actual needs.
4,Don't need to adjust the safety valve after starting the pump, for cracking pressure of safety valve has been adjusted in the factory test. You may adjust activated pressure according to your needs. You only need to unscrew or tightening screw of the main
5,Install filters in front of the pump suction, the filter specifications should be about 30 meshes, and the total flow area of filter should be 3 to 8 times that of the pump suction. A check valve should be installed on the outlet pipe road.
6,All the sizes, such as pipelines and pump, gate valve and exits and entrances of pump should be match, otherwise it will affect the pump performance. Too small pipe diameter, high vacuum degree and internal pressure of the pump will increase power consumption, it also affect the pump's service life.
7,All the pipeline valve should be opened before starting the pump. All the pipeline interior should be cleaned up for the first booting, to prevent debris into the pump and affect its normal work.
8,The pump should be filled with the transport medium before starting. Pay attention to the vacuum degree of the pump, such as no vacuum, high vacuum degree, no suction and other phenomena occure, the machine should be stopped immediately and checked it. Pump starting time is no more than one minute.
9,Pay attention to the working state of pump,if the machine occurs the abnormal sound, overheating and other phenomena, the staff should stop the pump immediately and check.
10,Operation time of air pump shall not exceed five minutes when the pump is stripping. The pump should be stopped and then rebooted if operation time of air pump is more than the stripping time.
11,Gearbox oil level should be within the prescribed scope, lubricating oil should be used medium Load No. 150 industrial gear oil, and the gearbox oil temperature shall not exceed 60oC.
12,Using lithium based grease as bearing lubricating oil, refueling once per shift.
13,Remaining medium should be drained after stopping the pump for fear of freezing parts in the cold season.
14,A leaking pipe is installed under the shaft bracket of integral screw pump, it is used to check the pump seal leakage. Stop the pump immediately and examine it if a leak occurs, and collect the minor leaked oil with ordinary containers if no time repair it, but it can't be sealed it or connected to the other pipe for fear that medium flows into the bearing cavity and burns bearing.
15,When the flow rate of screw pump is more than 400 m3/h, gear box are equipped with the cooling pipe of the circulating water to reduce the working temperature of the gear box. The cooling pipe of circulating water must be connected during installation, the cooling water circulation rate is about 2 m3/h.
16,The user should specify transport medium when they place an order to us.
Common problems and solutions
1,Pump can't suck oil or its discharge can reach the rated standard:As the air leakage of inlet pipe, so that the vacuum degree did not meet the requirements. Replace flange gaskets and tighten the flange bolts to seal completely;The large gaps between the pump body and the screw portion that caused too low vacuum degree. Replace the screw,or change the pump body,or replace the fuel inlet filter;The vacuum degree is too high due to the blockages of the fuel inlet filter and the oil channel. Clean the filter to eliminate blockages;No adjusting the opening pressure of the safety valve, or spring fatigue, or starting in advance that caused internal circulation. Restart pressure or replace the spring;The safety valve occurs no seal phenomenon due to debris. Clear the debris to meet the sealing requirements.
2,The pump produces abnormal sound, smoking, downtime, motor overload, and high specified values of the bearing and gear:The active and passive screws have collisions with pump body due bad bearing. Replace bearing;The circumferential direction of the active and passive screws is damaged by the gear wearing, then screws moved and produced collisions. Replace gear and adjust the circumferential direction of the active and passive screws according to the backlash;The motor is stopped by debris of pump chamber. Clean up the debris in the pump and maintenance machinery by debris;The gear box is lack of oil, or the oil level is too high. Fill in the oil or oil appropriatly according to the oil standard position.
Disassembly steps of maintenance screw pump
1,Disassembly steps of pump output shaft end
Remove the coupling and take out the flat key;
Take down the shaft covers of both ends, bearing pressed nut and check out the gasket.
Remove nuts on the shaft and a positioning, then exit shaft bracket with screw.
Take down the shaft bearings.
Remove the block and oil seal gland and take out the the oil seal gland.
Check and replace the damaged parts in time. (Pay attention to adjustment the position of shims on screw shaft.)
2,Disassembly steps of left pedestal parts
Remove the gear box and take down the gear pressing nut.
Take down the shaft frame ( the following steps are the same as the output shaft end)
accessories with pump
a product specification
a product certificate
two pieces of Inlet and outlet flange
a set of coupling
2CLG SERIES DOUBLE SCREW PUMP COMMONLY USED SPECIFICATION TABL
Center height h